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1.
Electric fields of the anions, cations and neutral forms of 2-aminopurine and 6-thioguanine have been mapped. Certain important
features of the maps are similar to those found earlier in the neutral and ionic forms of adenine and guanine. The computed
electric field patterns satisfactorily explain reactive sites and biological activity of the molecules. 相似文献
2.
The occurrence of charge on recoil56Mn produced by the (n,γ) reaction in polycrystalline potassium permanganate has been examined using the ‘charge plate technique’.
From considerations of capture gamma ray decay schemes and internal conversion it appears that, in a condensed medium, the
recoil atom develops charge after losing much of its initial kinetic energy which allows collection on charged electrodes.
Preliminary findings were presented at the International Symposium on Radiochemistry and Radiation Chemistry, RC-41 BARC,
Bombay, Feb. 4–6 (1991). 相似文献
3.
4.
Vijay K. Goyal Rakesh K. Kapania 《International Journal of Solids and Structures》2008,45(10):2799-2817
Because of the inherent complexity of fiber-reinforced laminated composites, it can be challenging to manufacture composite structures according to their exact design specifications, resulting in unwanted material and geometric uncertainties. Thus the understanding of the effect of uncertainties in laminated structures on their static and dynamic responses is highly important for a reliable design of such structures. In this research, we focus on the probabilistic stability analysis of laminated structures subject to subtangential loading, a combination of conservative and nonconservative tangential loads, using the dynamic criterion. In order to study the dynamic behavior by including uncertainties into the problem, three models were developed: exact Monte Carlo simulation, sensitivity-based Monte Carlo simulation, and probabilistic FEA. These methods were integrated into the existing finite element analysis. Also, perturbation and sensitivity analysis have been used to study nonconservative problems to study the stability analysis using the dynamic criterion. 相似文献
5.
π-electron SCF-MO theory in its variable electronegativity formalism has been applied to some monosubstituted benzenes. Calculated charge densities and bond orders for the ground and the first excited electronic states are correlated with chemical reactivity and the changes in molecular geometry on electronic excitation. The calculated results for spectra are compared with those obtained using the PPP method and also with the available experimental data. 相似文献
6.
7.
Kulwant Singh Kawaldeep Vijay Kumar 《Journal of Radioanalytical and Nuclear Chemistry》1998,231(1-2):45-50
The sum peak at 437 keV (356+81 keV) has been measured in various chemical and physico-chemical environments. The fact that
the intensity ratio of the sum peak to its single peak changes with the circumstances in which the radioactive source is placed
is used to observe the effect of the chemical environment on directional correlation coefficients of 351–81 keV cascade in133Ba−133Cs decay and to detect the variations in the electric field gradient in different barium compounds. The sum peak method has
been found to be useful in describing the chemical influences onG
22 parameters and hence in the study of electric field gradients. 相似文献
8.
Vijay Kumar Kawaldeep K. Singh 《Journal of Radioanalytical and Nuclear Chemistry》1992,166(2):131-142
The sum peak method has been applied to electron capture probability changes to the 1086 keV level in the decay of152Eu in the different environments, e.g. ethylenediaminetetraacetic acid (EDTA), bovine serum albumin (BSA) and hydrochloric acid (HCl). An attempt is also made to determine the effect of chemical environment on the directional correlation coefficient of the 1409–122 keV - cascade in152Eu 152Sm decay. A change of G22 is found in the different chemical forms. 相似文献
9.
An efficient synthesis of [1,3]oxazino[2,3-a]quinoline derivatives via a three-component reaction of quinoline, DMAD and carbonyl compounds is described. 相似文献
10.
Arroyo CG King BJ Bachmann KT Bazarko AO Bolton T Foudas C Lefmann WC Leung WC Mishra SR Oltman E Quintas PZ Rabinowitz SA Sciulli FJ Seligman WG Shaevitz MH Merritt FS Oreglia MJ Schumm BA Bernstein RH Borcherding F Fisk HE Lamm MJ Marsh W Merritt KW Schellman HM Yovanovitch DD Bodek A Budd HS de Barbaro P Sakumoto WK Kinnel T Sandler PH Smith WH 《Physical review letters》1994,72(22):3452-3455